Drill bit



0. PHIPPS Jan. 11, 1944.

DRILL BIT Filed June 10, 1943 2 Sheets-Sheet l T/ H E WU w /u B 0 0.PHIPPS Jan. 11,1944.

DRILL BIT 2 Sheets-Sheet 2 Filed June 10, 1943 Patented Jan. 11, 1944Orville Phipps, Denver, 0010., ass tnor to Central Mine Equipment Co.,St. Louis, Mo., a corporation of Missouri Application June 10, 1943,Serial'No. 490,292

2 Claims. (01. 25569) This invention relates to drill bitsi and hasspecial reference to rotary drill bits and augers for operating inminerals.

Objects of the invention are to provide an improved drill bit fordetachable connection with one end of a rotary spiral screw auger, andinterengageable portions on the adjacent ends of the auger and the bit,functioning for the purpose of preventing relative rotation of thebitand auger, and also functioning for the purpose of feeding chipped orwaste particles loosened or formed by operation of the drill through themineral along the bit and thence along the auger; to provide meanswhereby said interengageable portions additionally function to reinforceand strengthen the connection between the bit and the auger; to providean inclined waste feed device on the bit interengageable with the spiralof the auger in a manner to effect free and easy feed and movement ofthe chipped or waste material along the auger, and to prevent cloggingof said material at the bit; and to provide a bit having hard removableand replaceable cutting blades integrally attached to the forward facesof the bit arms so that, when any blade or blades become worn ordamaged, they may be removed and others substituted therefor.

Other objects will be apparent from the following description, referencebeing made to the annexed drawings, in which- Fig. 1 is a side elevationof my improved drill bit attached to the end of an auger.

Fig. 2 is a side elevation, viewed at right angles to the bit as shownin Fi 1, and more clearly showing the combined interlock and materialfeed.

Fig. 3 is a side elevation showing the diametrically opposite side ofthe drill bit from that shown in Fig. 1.

Fig. 4 is an end elevation of the bit.

Fig. his a side elevation like Fig. 6, showing a drill bit having ashank of modified construction. Fig. 12' is a cross-sectional view ofthe auger and shank of the drill bit similar to Fig. 5, and showing theshank an'd auger socket of modified construction. My improved bit,whether provided with the cylindrical shank shown in Fig. 6 or with thehexagonal shank shown in Fig. 11, comprises two,

arms I projecting forwardly in parallel planes and integrally united bya rearwardly tapered body connection 2. The outer walls 3 of the arms Iare uniformly and symmetrically curved on eccentric arcs, which arcs arealso eccentric to the axis 4 of the bit. As shown in Fig. 4, the bit isintended to be rotated in a counterclockwise direction. The walls 3curve outwardly and forwardly, uniformly and symmetrically, from theirrear longitudinal edges 5 to their forward longitudinal edges, so thatthe outer edges 5' of the cutting'blades 6 are spaced farther from theaxis 4 of the bit than are the rear edges 5. e The longitudinal edges 5and 5' are parallel. The side cutting edges 5' of the blades 5 definethe diameter of the hole drilled by'the bit while the walls 3 of the bitarms'l curve inwardly away from the wall of the hole formed by the bit.The edges 5 of the screw spiral I is in continuation of the outer orperipheral surface of the screw spiral 9 of the auger Ill to which thebit is intended to be attached. By this construction,:the forward Fig. 5is a cross-sectional view on the line 5-5 of Fig. 2.

Fig. 6 is a side elevation of the drill bit as shown in Fig. 2, detachedfrom the auger.

Fig. 7 is a side elevation of a portion of the drill bit detached fromthe auger as in Fig. 3, a part of the shank being shown in section.

Fig. 8 is a side elevation of the attaching end portion of the augerapart from the drill bit, a part of the socket being in section.

Fig.9 is a view similar to Fig. 8, showing the attaching end portion ofthe auger turned about outer cutting edges 5 of the blades 6 are beyondthe plane of the periphery of the screw spiral 9 far enough to drill ahole substantially larger than the diameter of the screw spiral tofacilitate rotation of the bit and feed of the chips and waste materialby and along the auger."

The body 2 or integral connection between the arms I is formed with asharp or attenuated forward edge II from which the walls I2 of said bodyconnection diverge outwardly and rearwardly from the axis 6 of the bitto the cylindrical abutting portion I3 of greater diameter than thediameter of the shank 8 and having approximately the same diameter asthe end of the auger socket II which receives said shank 8. One of thewalls I 2 also intersects the outer side of the screw spiral I, asshown, so that the waste material passing along said wall I2 is receivedby and caused to move along said screw spiral I. The

socket I4 is of greater outside diameter than the outside diameter ofthe auger ill with which it is integral, and the auger screw spiral 9continues along said socket and is formed with a thicker end portion I5which substantially strengthens the socket l4 and forms a stronginterlock with the bit. When the shank B is extended into the socket idin proper position;, the, circumferentially inclined end of the bitscrew spiral \fl' is.

received within an inclined notch id in the end of the socket It inabutting contact with'the end portion it of the screw spiral 9. Thus,the outer walls or peripheral surfaces oi the screw spirals l and El arealined, and the curved or abutting ends of the spirals l and d formcurved and suh= stantially smooth feed surfaces for the material cut orchipped by the bit In assembly, the end of the shank preferably abutsagainst a shoulder at the inner end of the socket l4 while a cylindricalaxial. extension if; of said shank projects beyond the end thereof intothe body of the tubular auger Ml. When the end of the screw spiral l isengaged in the notch 16, a radial hole is through the extension itregisters with a radial hole 2t through the end of the tubular auger illin order to receive a retaining pin 2i. When the bit is properlyassembled on the end of the auger as described and as shown in thedrawings, the pin 2i may be driven or forced into the holes 2t and illand irictionally retained therein to hold the bit positively inconnection with the auger and prevent accidental detachment. When it isdesired to remove the bit iromthe auger for any purpose, the pin it maybe driven out, leaving the bit freely detach able from the auger.

' The cutting blades t are of very hard synthetic alloy and are weldedor brazed on the arms i in parallel planes and at opposite sides of thediametrical plane of the bit extended parallel to the forward surfacesof said blades (Figs. 1 and 3). The blades 5 are of equal width and havetheir inner edges equidistant from and alined with the sharp orattenuated edge i i. This provides means facilitating feed of themineral chips and particles along the inclined walls id to the spirall-9. This construction prevents clogging of the waste material at theend of the bit.

In the modified specific form of the invention shown in Figs. 11 and 12,the cylindrical shank 8 With its cylindrical extension it are omitted.Instead, a hexagonal shank 22 is formed integral with the cylindricalabutting portion iii of the bit body, and has a hexagonal extension, 23projecting beyond the end thereof. The sides of the hexagonal shank 22and hexagonal extension 23 are in parallel planes. Said shank 22 isdesigned and adapted to fit Within a complementary hexagonal socketwhile' the hexagonai'extension it extends into a complementarily shapedend portion of the auger Ill, and the end of the cylindrical abuttingportion l3 of the bit abuts and seats against the end of the auger it.The extension 23 is formed with a hole 24 adapted to register with ahole 25 in the auger when the bit and auger are properly assembled andthe end oi the screw spiral l is engaged in a notch it. The hexagonalshank 22 and hexagonal extension til coopcrate'directly with theinterlock comprising the abutting ends of the screw spirals l nd 9 andthe notch. it receiving the end of the so v. spiral i. A pin 28 driveninto and through the holes lid and 25 functions as does the pin ii tohold the bit in connection with the auger and prevent accidentaldetachment of the two,

From the foregoing, it is apparent that my improved bit operates andfunctions very efficiently and feeds the chipped or waste particles bydirect cooperation of the bit structure with the auger screw. Thespecific arrangement and abutting interengagement oi the bit screwspiral l with the end of the auger screw spiral ll provides a verystrong interlock that will resist breakage at these points. cases wheregreater or maximum strength is required for drilling into the hardestminerals, the hexagonal shank 22 may be used to fit Within acomplementarily shaped socket in the end of the auger and cooperatedirectly with the interlocked screw spirals to prevent breakage underthe severest uses, Feed of the chipped or waste particles which areloosened or formed by operation of the drill is facilitated by thediverging walls l2, and the attenuated or sharp edge I l formed byintersection of said walls between the arms l. l contemplate equivalentvariations from the structure disclosed as may be required to adapt theinvention to pre ferred forms,

I claim:

1. In a metallic drll bit comprising a rearwarch ly tapered body havingtwo arms projecting forwarclly therefrom and separated by an interveningspace; a screw spiral formed integral with said body rearwardly beyondsaid arms and extending rearwardly beyond the rear end of said body, anda shank integral with the end of said body and with said screw spiralfor extension into the end of an auger for which said bit is intendedand having a notch in its end for receiving the end of said screwspiral.

2. A drill comprising an anger, a socket integral with one end of saidauger having a notch in one side'thereof, a screw spiral integral withsaid auger having an end at the rear side wall of said notch, a bitabutting against the end of said socket and having a shank extended intosaid socket, and a screw spiral integral with said body and said shankengaging in said notch and against the end of said first screw spiralwhen said shank extends into said socket.

ORVILUE PHIPPS.

